
 Start

132386
 Prefix

If we can make a guess at these two factors, that is, intraclass correlation and cluster size, we can adjust our sample size
calculations by multiplying the variance of the sample size formulas by the following correction
 Exact

(Kish 1965)
 Suffix

+(m1)
wherem=average number of observations per cluster,=intraclass correlation
If there is no intraclass correlation, that is,=0, this correction factor reduces to 1, thus causing no increase in the sample
size estimate.
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